Improved Bone Conduction and Hearing Outcomes After Stapes Surgery for Otosclerosis

To evaluate the improvement in bone conduction (BC) thresholds after stapes surgery for otosclerosis, compare the outcomes of surgical techniques, and analyze the short- and long-term results to inform treatment strategies.

We retrospectively reviewed data from 173 patients (188 ears) who underwent total stapedectomy, partial stapedectomy, or stapedotomy for otosclerosis between 2009 and 2024. Medical histories, preoperative evaluations, and operative records were analyzed, focusing on pre- and postoperative pure-tone audiometry.

Postoperatively, mean thresholds improved by 20.3 dB for air conduction (AC) and 2.0 dB for BC, leading to a mean air-bone gap (ABG) of 18.3 dB. An ABG of less than 10 dB was achieved in 79 ears (42.0%), and full ABG closure (ABG ≤ 20 dB) was achieved in 145 ears (80.4%). Compared with the preoperative levels, the BC thresholds at 0.5, 1, and 2 kHz improved by 1.3, 3.7, and 4.9 dB, respectively. However, the 4-kHz BC threshold increased by 1.7 dB. Postoperative AC thresholds at 0.5-4 kHz decreased significantly by 27.1, 26.5, 18.3, and 9.2 dB, respectively (p < 0.001).

Stapes surgery significantly improved BC thresholds at 0.5, 1, and 2 kHz in patients with otosclerosis, with resolution of the CN at 2 kHz, indicating correction of the CHL. Although a slight increase in the BC threshold was observed at 4 kHz, the overall AC threshold improvement and ABG closure were substantial. These findings highlight the clinical relevance of the postoperative BC threshold dynamics.